Fitness cost associated with resistance to fluoroquinolones is diverse across clones of Klebsiella pneumoniae and may select for CTX-M-15 type extended-spectrum β-lactamase

Lowered fitness cost associated with resistance to fluoroquinolones was recently demonstrated to influence the clonal dynamics of methicillin-resistant Staphylococcus aureus (MRSA) in the health care setting. We investigated whether or not a similar mechanism impacts Klebsiella pneumoniae. The fitness of K. pneumoniae isolates from major international hospital clones (ST11, ST15, ST147) already showing high-level resistance to fluoroquinolones and of strains from three minor clones (ST25, ST274, ST1028) in which fluoroquinolone resistance was induced in vitro was tested in a propagation assay. Strains from major clones showed significantly less fitness cost than three of four fluoroquinolone-resistant derivatives of minor clone isolates. In addition, plasmids with CTX-M-15 type extended-spectrum β-lactamase (ESBL) genes were all retained in both major and minor clone isolates, irrespective of the strains’ level of fluoroquinolone resistance, while each plasmid harboring SHV-type ESBLs had been lost during the induction of resistance. Major clone K. pneumoniae strains harbored more amino acid substitutions in the quinolone resistance determining regions (QRDRs) of the gyrA and parC genes than minor clone isolates. The presence of an active efflux system could be demonstrated in all fluoroquinolone-resistant derivatives of originally SHV-producing minor clone isolates but not in any CTX-M-15-producing strain. Further investigations are needed to expand and confirm our findings on a larger sample. In addition, a long-term observation of our ciprofloxacin-resistant minor clone isolates is required in order to elucidate whether or not they are capable of restoring their fitness while concomitantly retaining high minimum inhibitory concentration (MIC) values.     

Intraparental Inconsistency: The Influence of Parenting Behaviors on Aggression and Depression in Children

The authors examined several different predictive and mediation models of longitudinal parental inconsistency over a 3‐year time span. They hypothesized that parental behavior (communication/affection, kindness, and positive control) mediated the relationship between parental inconsistency (mother or father) and two emotional problems in children: (a) aggression and (b) depression. Data were obtained from a 3‐wave study (2007, 2008, and 2009) of 523 Spanish families with children ranging from 9–15 years of age at the beginning of Wave 1 (41.3% boys). Structural equation models revealed that multiple dimensions of parenting (mother or father) fully or partially mediated the relationship between longitudinal parental inconsistency and the child's adjustment. Communication/affection and kindness are the main processes through which parental inconsistency affects a child's aggression and depression. These results represent an important contribution to the improvement of parenting models of relationships between parental inconsistency and child adjustment.     

Pupil motility in long-term diabetes

Summary Employing infrared TV-videopupillography and the open loop stimulatory technique the ability of the pupil of the eye to react to rhythmic light stimuli of increasing frequencies was studied in 15 control subjects and 14 long-term juvenile diabetics. The degree of retinopathy varied from nil to proliferative changes. The visual acuity of all subjects studied was at least 6/9 and there were no ophthalmoscopic signs of retinopathy in the area stimulated by the light, thereby ensuring roughly uniform retinal sensitivity. The degree of neuropathy ranged from nil to moderate or severe as judged by vibratory perception threshold and pupil size. The pupil response (gain: fractional response to a unit light stimulus, and phase lag: latency period in number of stimulatory cycles) was the same in the group of diabetics as in the control group. The results show that the pupillary abnormalities of long-term diabetic patients (small size and a loss of spontaneous fluctuations) are probably] not due to stiffness of the iris tissues. It is suggested that diabetic autonomic neuropathy predominantly affects the sympathetic innervation to the dilator muscle, the parasympathetic innervation to the sphincter muscle being relatively spared.     

Serological abnormalities in juvenile chronic arthritis: a review of 46 cases.

Data of 46 patients with juvenile chronic arthritis were evaluated. All of them were under the age of 16 at the time of study. Patients with juvenile ankylosing spondylitis, psoriatic arthritis, and arthritis associated with inflammatory bowel disease were excluded from this series. Twenty-six patients had pauciarticular, 9 had systemic, 8 had polyarticular, and 3 patients had seropositive 'adult type' JCA. In all patient groups IgG, IgM, IgA, and C3 levels were significantly higher than in the control group. None of the controls but 13 of 46 patients had high IgE levels. IgA and IgG values were significantly higher in the seropositive subgroup than in the pauciarticular subgroup. There was no other positive correlation between levels of immunoglobulins, C3, and clinical features of disease. Platelet counts were significantly higher in patients with active disease. In the control group 4 out of 10 children had 'hidden' rheumatoid factor. All these children with positive findings were young.